There has been known the so-called link copy operation for concurrently executing a print job with two or more units of image formation apparatus by linking a plurality of image formation apparatuses such as digital copying machines through a communication network like LAN and selecting a link mode provided in each apparatus. In other words, in this link copy operation, for instance, when a specified number of copies are to be prepared for a document having N pages and further the processing for stapling (staple mode) is to be executed, then the availability of a staple function in a local machine (master machine) and other machines (slave machine) is checked. When it is confirmed that the link mode and staple mode are available in the local machine and other machines, then the printing job is executed by all the machines concurrently.
Further, there have been proposed various types of system for various purposes in which a plurality of image signal output units such an image scanner capable of outputting an image signal, a word processor, and a personal computer and a plurality of image formation units such as printers capable of forming an image based on image signals outputted from the image signal output units.
As examples of the image formation system described above, there is, for instance, the image formation system disclosed in Japanese Patent Publication No. HEI 2-21190 in which a plurality of image signal output devices and a plurality of image formation apparatuses are connected to each other in order to perform recording, storage and communication of image information between all the apparatuses. In this system access from an apparatus to any other apparatus is possible. Further, there is the system disclosed in Japanese Patent Laid-Open Publication No. HEI 5-304575 in which a plurality of digital copying machines are connected to each other to realize a faster copying.
In the conventional technology as described above, however, when system configuration of the master machine is different from that of the slave machine, if a mode not available in the slave machine is set in the master machine and link copy is started, a result which is different from that specified by the user is obtained. Thus there is a problem that operational disturbance or generation of incorrect copy may occur in the link copy operation.
In the link copy operation based on the conventional technology, each time an operation in the link copy mode is to be executed, it is required to directly check various conditions (such as availability of supply, a communication state, a state of a display screen, and an operating state) in the slave machines and then to set the link copy mode or start the operation. Because of such requirements, the operation is very complicated and productivity in printing is disadvantageously lowered.
In the link copy operation based on the conventional technology a function for automatically starting the link copy operation in both the master machine and the slave machines is not available. Therefore, when the number of copies is large, a long time is disadvantageously required for executing the printing job and the operation is also very complicated.